I made a brush-less LST. I used a cheap mystery 100a ESC that I got on ebay for 27.00 shipped. The funds were tight at the time of this build. it was a little over a year ago. It was hard to program. I used a 14.8 cell battery stock transmission a feigao 8xl motor and mechanical brake. The pinion/spur I have are 25/63 I used the fine design kit for my build. I think you will no problem hitting 40 mph. I never tested out doors due to the esc. I have a home made dyno that I can strap it down too and it seems fast. But I really don't know? It has big Joe tires w/ 23mm wheels on it. Its BIG. Will take it out soon. I would post a pic but not sure how too on this forum?